An apparatus for forging parts, particularly forged rotationally asymmetrical parts by warm or hot forging, comprising at least one upper part, at least one upper die half as well as at least one lower die half and at least one lower tool, at least a first closing apparatus and at least a second closing apparatus, wherein the upper part and the lower tool are provided in a working space delimited by a press ram and a press table and can be moved relative to one another between a starting position and a closed position.
The invention furthermore relates to a press for forging parts, particularly forged rotationally asymmetrical parts by warm forming or hot forming. Presses of this type are usually used as multi-stage presses in a burr-free forging method.
Die-forging presses for burr-free forging, particularly of rotationally asymmetrical parts, are used more and more frequently, above all for the automotive industry, because the weight of the components can be reduced by a shape that does not have rotational symmetry. During die forging, preferably burr-free die forging of rotationally asymmetrical parts, the upper die half is normally pressed down against the lower die half, thereby closing the die. Shaping takes place using at least one further pressing punch, called the knockout punch. The knockout punch is normally rigidly fixed in place, so that for shaping, the two die halves are moved relative to the knockout punch. This takes place in that the press ram on which the upper die half is usually fixed in place presses down against the lower die half, and the two die halves are moved downward and thereby relative to the knockout punch.
Such an apparatus is known, for example, from US 2002/0040589, in which die forging takes place between an upper and a lower die respectively supported on an upper and a lower tool. A first closing apparatus and a second closing apparatus, which are provided between the tool parts or on the lower tool, allow reliable filling of the mold for the forging process. The closing force is adapted to the required pressing force progression required for complete filling of the tool, by two closing apparatuses that exert different closing forces.
However, a disadvantage of the solutions known from the state of the art is a decidedly complicated and expensive tool structure, which has a plurality of individual parts in the working space, in other words in the space that is formed vertically by the closing dimension of the press and horizontally by the outer dimensions of press table and press ram.
The required construction space of the devices known from the state of the art accordingly does not permit any automatic forged part transfer and also hinders the use of usual manipulators for spray application of cooling and/or lubricating media.
This leads to the necessity of designing new and complicated peripheral systems for operation of such forging apparatuses. Also, in the case of unforeseen malfunctions, functional parts of the apparatus can be destroyed due to the closeness of the components of the closing apparatus to the tools, and as a result the system must be shut down for an extended period of time.
A further disadvantage of that the solutions previously known from the state of the art is that they only allow the use of comparatively slight closing forces, and that a not insignificant introduction of heat from the forging process into components of the closing apparatus, particularly ring pistons, cylinders, seals or piston accumulators takes place. This results in more rapid wear of the seals, connected with undesirable leaks.
Finally, rapid tool replacement is also prevented due to the arrangements known from the state of the art.